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A Sunday hike in the Brooks Range, Alaska, about 1980-81. The woman is Barbara Lachenbruch (student of Terry Chapin's, Univ Alaska). Behind her is Tom and Ellen (last names unknown), working at Toolik Lake at the time.

Left to right: Jim Laundre, Anne Giblin, Gus Shaver, and Knute Nadelhoffer, in a snowstorm at Toolik Lake, July 18, 1984. Jim was then an RA, Anne, Gus, and Knute were Assistant Scientists, all at the Ecosystems Center.

This is a Winogradsky column that Joseph Vallino uses in a SES course on Methods in Microbial Ecology. Almost every bacterial metabolic process that occurs on Earth also occurs in these columns that are simply constructed by placing freshwater or marine sediments augmented with a carbon source (such as saw dust) and fertilizer (N and P) in a column and topping it off with either fresh or sea water. Julie Huber is a co-instructor in the course.

These are methanotrophic microcosms that are being used to develop and test new approaches to modeling microbial biogeochemistry using thermodynamic approaches (namely, the principle of maximum entropy production).

Caption reads: "Figure 4: A diagrammatic model of carbon and nitrogen flow in an estuarine ecosysem that emphasizes inputs of organic carbon and nitrogen and inorganic nutrients from upland watersheds and processing by the estuarine food web. Compartments of the mathematical model are shown in the box. The inorganic nutrients compartment comprises both ammonium and nitrate. The organic matter compartment comprises three distinct components: labile nitrogenous material, labile carbohydrate material and refractory nitrogenous materal."

Caption reads: "Figure 1: The dashed lines mark two catchments (watersheds) at the Bear Brooks Watersheds site in Maine. Both catchments are located on a southeast-facing slope and drained by streams that persist throughout the year (dark lines). The shaded catchment was treated with fertilized labeled with 15N during 1991; the other served as a control. Filled trianges show sampling locations in the fertilized area."